A load control device for controlling the power delivered from an AC power source to an electrical load includes a thyristor, a gate coupling circuit for conducting a gate current through a gate of the thyristor, and a control circuit for controlling the gate coupling circuit to conduct the gate current through a first current path to render the thyristor conductive at a firing time during a half cycle. The gate coupling circuit is able to conduct the gate current through the first current path again after the firing time, but the gate current is not able to be conducted through the gate from a transition time before the end of the half-cycle until approximately the end of the half-cycle. The load current is able to be conducted through a second current path to the electrical load after the transition time until approximately the end of the half-cycle.

Controlling power delivered to a heating device occurs using a phase control, wherein the phase control includes changing a cut-off phase of an alternating current electrical signal delivered to the heating device. The power delivered to the heating device is increased from zero to an operational level using the phase control. The level of the power delivered to the heating device is maintained at the operational level using both the phase control and an integral half cycle control. The integral half cycle includes selectively removing a plurality of half cycles from the alternating current electrical signal delivered to the heating device.

The present invention allows individual control of an output voltage of a main transformer and an output voltage of a teaser transformer while utilizing output characteristics of the respective transformer when a Scott connected transformer has control equipment arranged on the input side thereof, including first control equipment arranged in one of two phases of the main transformer on the input side in order to control a voltage or a current and second control equipment arranged in one end of a primary coil of the teaser transformer on the input side in order to control a voltage or a current, the control equipment controlling an output voltage of the main transformer and an output voltage of the teaser transformer individually.

A dimmer is provided for controlling power to a load, the dimmer having a ground leakage power supply deriving power from a connection of the dimmer to ground. The power supply may be a switching-mode power supply that can be the sole or primary power supply to power operation of the dimmer, including operation of the controller.

A power supply apparatus includes a first circuit, a second circuit, a switcher configured to switch between a power supplied state and a power interrupted state, a driver configured to output a signal for switching the state of the switcher, an adjusting unit, a first control unit, a second control unit, a first communication portion, and a second communication portion. The first control unit is operated by power supplied by a signal generated in the first communication portion. The first control unit transmits, to the second communication portion, information about a detection result. The second control unit controls the adjusting unit based on the information. The first control unit outputs a predetermined signal for causing the driver to output the switching signal for putting the switcher into the interrupted state in a case where abnormality occurs. The driver outputs the switching signal for putting the switcher into the interrupted state based on the predetermined signal.

A hub device and a power supply method thereof are provided. The hub device includes a power input port, first and second power output ports, a power management circuit and a controller. When first and second electronic devices are respectively connected to the first and second power output ports, the controller determines an input electric power from at least one default supply power of the power adapter based on first operating power information of the first electronic device and second operating power information of the second electronic device, so as to control the power adapter to provide the input electric power to the power input port. The power management circuit receives the input electric power to generate first and second operating power, so as to output the first operating power to the first power output port and output the second operating power to the second power output port.

A power supply unit for use with thermostats or other like devices. The power supply unit may keep electromagnetic interference emissions and harmonics at a minimum. A unit may have enough power for triggering a switch at about a cross over point of a waveform of input power to the unit. Power for triggering may come from a storage source. Power for the storage source may be provided with power stealing which require switching transistors which can generate emissions. In-line thermostats using MOSFETS power steal may do the power steal during an ON state (triac, relay or silicon controlled rectifier activated). Gate signals to the transistors may be especially shaped to keep emissions from transistor switching at a minimum. All that may be needed, during an OFF state as a bypass, is a high voltage controllable switch. The need may be achieved using high voltage MOSFETS.

A power converter for heat tracing applications is disclosed. The power converter includes a controller configured to control an input switching stage. The power converter also includes an output filter, the output filter electrically coupled to the input switching stage. Further, the power converter includes a passive cooling element, the passive cooling element coupled to the power converter. The controller is configured to select a peak voltage and set a power converter output voltage based on at least one of the peak voltage and a power converter input voltage. The passive cooling element is configured to decrease a temperature of the power converter and to obviate the need for cooling with moving parts, making the system viable for hazardous areas in addition to non-hazardous areas. The input switching stage includes a plurality of transistors. The power converter output voltage and the power converter input voltage are both alternating current.

A power supply apparatus includes a first circuit, a second circuit, a switcher configured to switch between a power supplied state and a power interrupted state, a driver configured to output a signal for switching the state of the switcher, an adjusting unit, a first control unit, a second control unit, a first communication portion, and a second communication portion. The first control unit is operated by power supplied by a signal generated in the first communication portion. The first control unit transmits, to the second communication portion, information about a detection result. The second control unit controls the adjusting unit based on the information. The first control unit outputs a predetermined signal for causing the driver to output the switching signal for putting the switcher into the interrupted state in a case where abnormality occurs. The driver outputs the switching signal for putting the switcher into the interrupted state based on the predetermined signal.

Provided is an electronic device which can easily measure a standby current of an internal circuit of an electronic device after burn-in. The electronic device includes: a power source terminal; a regulator that generates a predetermined voltage from a voltage of the power source terminal; an internal circuit that is operated by an output voltage of the regulator; and a standby terminal through which the regulator and the internal circuit are set to a low power consumption state.